Method of making brake-shoes.



PATENTED SEPT. 22, 1903.

W. D. SARGENT. METHOD or MAKING BRAKE snons.

APPLICATION FILED F113. 13, 1903.

K0 MODEL.

THE Nana's Pmas c0. momunn. WkSHNOTON. A c.

UNITED STATES Patented September 22, 1903.

PATENT OF ICE.-

WILLIAM DURHAM SARGENT, OF NEW YORK, N. Y., ASSIGNOR TO AMERICAN BRAKE SHOE 85 FOUNDRY COMPANY, OF

TION OF NEW JERSEY.

NEW roams. Y., A CORPORA- METHOD OF MAKlNG BRAKE-SHOES.

' SPECIFICATION forming part of Letters Patent No. 739,791, dated September 22', 1903. ApplicationfiledI'ehruary13,'1903. Serial in. 143,218. (roman;

To all whom it may concern:

Be it known that I,W1LILIA M DURHAM SAB- GENT, a citizen of the United States, residing to such as in common use on railway-cars, and

especially to that style of shoe in which there is an insert of different metal designed to be exposed by wear and to improve the wearing qualities and durability of the shoe. A brake- 5 shoe of this general type is illustrated in my former United States patent, No. 516,992, in

which there is a plug or insert of metal of a greater degree of hardness than'that of the] main body of the'shoe and which is made by 29 casting the body of the shoe of softer metal with recesses and then pouring in the hard metal for the insert blocks. In mylater United States patent,No.'587,-l93, I have i1lustrated a method of makingin'serts of malle- 2 5 able expanded shoe and has been found to'verymuch improve the frictional resistance of the shoe.

The principal object of the present invention is to improve upon the structure of brake- 30 shoes by combining both'the qualities of the above-mentioned methods, securing the durability due to the hardened insert, and the increased friction due to the malleable metal embedded in the shoe. 7 i

A further object of the invention is to provide for the manufacture of a uniform quality of briquets or inserts and provide a conven' ient means for preserving the malleable metal from rust and to render easy the proper 4o proportioniug of the two metals and the proper placing of the malleable metal in the cast metal.

A further object is provide a process by which the briquets or inserts may be con- 45 veniently made at central distributing-stations and may be cheaply stored and packed and transported to the foundries where they are to be used in making of the complete shoe.

I attain the above objects, as well as other shoe of varying metal, which is cast in the advantages which will hereinafter appear, by means of the mode of manipulation described below, and illustrated in a preferred form in the accompanying drawings.

Figure 1 represents a perspective view and partial section of an iron mold used for easting the briquets. Fig. 2 is a partial section illustrating the mode of placing the expanded metal in the briqnet-molds. Fig. 3 -illustrates'a fragment of the form of malleable iron or steel which I- prefer to use.

Fig.4 is a perspective view of the finished briquet.

Fig. 5 is a plan view of the common brake shoe mold, showing the briquets in position therein ready to have the softer cast Fig. 6 is a perspective and metal poured in. central section of a complete brake-shoe,

showing the briquets or inserts therein and v the malleable metal embedded in the bri quets in section.

Asthe result of along series of experiments the trade has come to recognize it as imporwearing-s'urface of. a brakedegrees of hardness, and both hardened inserts and a series of embedded malleable filaments, such as expanded metal webbing, have comeinto very general use.

There are objections to the process of making brake-shoes by casting metal about a series oflayers of expanded metal in the mold partly because this is not economical in the use of expanded metal and it prevents the use of hardened inserts in the body of the softer cast metal, and, further, it is found to be'difficult to preserve the expanded metal from rustbetween the tant to have the On the other hand, the method of using hardened blocks has some disadvantages because the chill of the surface around them produces a harsh action upon the wheels and because the hardened metal alone decreases the frictional resistance of the brake.

In order to overcome many of these difiicul ties and others, I proceed as follows: I provide an iron mold a, having a series'of nests or depressions I) cut therein, of a proper shape, and in these I place the proper quantime of its mannfac ture and its actual use in making a shoe.

durable and suitable medium tity of expanded metal 6, placing the same so that the strands of different layers will alternate in longitudinal position, as shown in Fig. 2. These may be crowded irregularly into the mold, and since it is not necessary to cover the edges with cast metal there is no necessity for accurate cutting of the pieces to fit in the mold. Upon the top of the moldblock a I then place a convenient cover,'such as the iron plate 0, which is provided with a series of inlet-apertures d, and thereupon pour in the metal to embed the expanded metal therein and form the briquetf. (Shown in Fig. 4.) The contact of the cast metal with the iron mold chills the surfaceof the cast metal of the briquet, and this hardness is very useful to preserve the briquets from rust when they are stored in quantities. It is evident that both the relative quantities of malleable iron and of cast-iron and the quality of the cast-iron may be regulated at will and may be rendered perfectly uniform. The briquets f, which are the first or partial product of my process, may then be shipped to the vpointwhere it is desired to use them in the making of brake-shoes, and the subsequent step of the process may be carried out in any ordinary foundry with the ordinary apparatus. In carrying out the second step of placing the briquets in the shoe itself I may use any common form of sand mold, such as shown in Fig. 5, and the briquets being placed in proper position therein the softer cast-iron to form the body of the shoe is poured in, as will be readily understood. Upon contact with the molten metal the hardened surface of the briquets will be annealed, which will avoid the harsh action on the wheels which might otherwise result, and a good joint is secured between the two qualities of metal. In order to insure the proper retention of the briquets in place, I prefer to make them of a truncatedpyramid form. (Shown in Fig. 4.)

It will be evident that by this process I attain the greatest possible economy in the use of the expanded metal and make it easy to secure a perfectly-uniform quality of insert. At the same time the exact composition of the hard cast metal is under complete control. It is also very important that the expanded metal may be used upin making the briquets in quantities and so stored and packed as to prevent deterioration by rust. It is easy to insert the proper quantity of malleable metal in the-iron mold, and this renders accurate cutting of sheets of expanded metal or folding of the same unnecessary. Also the quality of the hard metal forming the briquet is less affected in this form by the molten iron used in making the complete shoe, the malleable metal is better protected, and isembedded in a more solid and more than when directly cast into the shoe. The advantages'of having these cast inserts made at a central distributing-point of uniform character and under complete control of an expert and the advantages in packing and transportation will readily occur to those familiar with the art. Since the total weight of the inserts will ordinarily be something like fifteen per cent. of the weight of the brake-block itself, it is also apparent that a great saving in the cost of transportation may be made, since the briquets may be used in any foundry by the simplest methods in forming the complete shoe; The peculiar mixture of the three grades of metal, as above described, attains the highest degree of durability combined with the best quality of friction-surface, and consequently the brake-shoes may be made of a uniform and an excellent quality without the necessity of employing expert labor in the casting of the final shoe.

While I have illustrated the particular form of the malleable metal which I prefer to use as the resistance-filaments in the shoe, it will of course be understood that any other form of metalsuch as wire, scrap cuttings, or any other form of filamentsmay be used indifferently, and While I generally find it advantageous for the reason stated to use an iron mold for the briquets and a sand mold in making the shoe this is of course not essential to my invention, and when the briquets are not desired to have a chilled surface any other suitable mold may be used.

Having thus described my invention, what I claim, and desire 'to secure by Letters Patent, is the following:

1. The process of making brake-shoes which consists in forming briquets or insert-blocks of cast metal containing filaments of malleable metal, and afterward placing said briquets or blocks in a mold and embedding the same by casting around them the metal to form, the body of the shoe.

2. The processof making brake-shoeswhich consists in providing a metal mold, placing therein a quantity of malleable metal, pouring in a quantity of hard cast metal to form a briquet, and thereupon placing a series of said briquets in a brake-shoe mold and embedding the same in a body of softer cast metal, substantially as described.

3. The process of making brake-shoes which consists in providing a briquet or insert composed of hard cast metal cast around a quantity of malleable metal, placing a series ofsaid briquets in a mold and casting softer metal therein to embed the said blocks, substantially as described.

4. The process of making brake-shoes which consists in providing an open metal mold of standard form and size, placing therein a quantity of expanded metal and casting thereon a quantity of hard iron to form a briquet, thereupon providing a brake-shoe sand mold, placing a series of said briquets therein, and pouring in soft cast-iron to embed the said .briquets in the body of the shoe, substantially as'described.

5. A brake-shoe comprising a body of soft IIO cast metal havingembedded therei'n briquets of harder cast metal, said briqnets containing a quantity of malleable metal. V 6. A brake-shoe comprisingaseries of filaments of malleable metal embedded in blocks of hard cast metal, and said blocks being embedded in soft cast metal forming the body 8. A brake-shoe briquetinsert consisting of a cast-metal block of truncated-pyramid form having embedded therein in the casting an approximately uniformly distributed series of filaments of malleable metal extending entirely through the block, substantially as and for the purpose described.

In testimony whereof I have hereunto signed my name in the presence of the subscribing witnesses.

WILLIAM DllRHAM SARGENT;

Witnesses WILLIAM GoNoVER, EDWARD MALLQWS. 

